Vertiv Liebert Mini-Mate MT036, Инструкция по установке и эксплуатации

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5. Over a period of time, the electrode surface becomes coated with a layer of insulating material,
which causes a drop in current flow. As this happens, the water level in the canister will slowly
rise exposing new electrode surface to the water to maintain normal output. Eventually, the
steady-state water level will reach the canister-full electrode and indicate so by activating the
canister full alarm and opening the humidifier contactor. At this point, all of the electrode
surface has been used up and the canister must be replaced.
6. After the entire electrode surface has been coated, the output will slowly begin to fall off. This
usually occurs in the last several hours of electrode life and should allow enough time to
schedule maintenance. During these last hours, the mineral concentration can increase. If the
mineral concentration is too high, arcing can occur. If the electrodes start to arc, turn off the
humidifier immediately and replace the canister with the identical part.
9.4.2 Replacing the Canister
The humidifier RUN/DRAIN switch is located in humidifier assembly. This switch should be in the RUN
position when the humidifier is in normal operation. It should be in the DRAIN position when a manual
drain for service is required. The electronic control board for the humidifier is located in the same area as
the humidifier assembly. When the unit is energized, power is available to the humidifier circuits.
1. Turn off the humidifier by lowering the humidity setpoint below the ambient humidity level.
Record the original setpoint.
2. Place the RUN/DRAIN switch in the DRAIN position to drain the water from the canister.
3. Return the RUN/DRAIN switch to the RUN position after the canister has drained.
4. Turn Off the power at the main unit.
5. Remove the cover from the humidifier cabinet
6. Locate the power wires to the steam canister. They are connected to the canister with 1/4-in
quick connects. Make note of the wiring configuration before removing any wires. Refer to the
schematic on the unit. Slide the rubber boot back to expose the connections. Remove the two
(2) power wires and the canister wire. Do not loosen the screws that secure the electrodes.
7. Loosen the steam outlet hose clamps and slide the steam hose away from the canister fitting.
8. Release the canister clamp along the base of the canister.
The canister is now ready to be removed.
9. Remove the canister.
10. Reverse these steps to replace the canister, taking special not of the following:
• When replacing wiring, connect the red wire from terminal #1 on the interface to the red
tip terminal on the canister. Reconnect the power wires as they were formerly connected
(#2 on the left and #1 on the right).
• Always check the fill and drain solenoids for proper operation after replacing the canister.
9.4.3 Circuit Board Adjustments
Humidifier operation is governed by the humidifier control board. There are three potentiometers
mounted on the board. These pots can be used to adjust for extreme water conductivity conditions and
capacity.
POT2 controls the amperage at which the drain will energize. The pot is clearly marked in percentages.
This adjustment is factory-set at 85%, which indicates that the unit will drain when the amperage falls off
to 85% of the capacity setpoint. Raising the value increases the frequency of drain cycles. Lowering the
value decreases the frequency of drain cycles. The frequency should be increased for highly conductive
water and decreased for less conductive water. If adjustment is necessary and a change of three to four
percent in either direction does not permit normal operation of the unit, consult your Vertiv supplier.
POT1 controls the duration of the drain cycle. The pot is clearly marked in seconds. This adjustment is
factory-set at 60 seconds and should not be readjusted without consulting your Vertiv supplier.
POT3 is factory-set at 100%. The maximum capacity of the system is not field adjustable.
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